Object Oriented Programming Practice Test: Default Arguments vs Overloading, Upcasting and Downcasting — Flashcards

Quiz on default arguments, constructors overloading, upcasting and downcasting.

In Object-Oriented Programming (OOPs), overloading is a fundamental concept that allows a class to define multiple methods with the same name but different parameters. Function overloading is more general than default arguments because overloaded functions can take different types of parameters. 

Here are some differences between default arguments and overloading:
Default arguments: A default argument is a value that the compiler inserts if it isn't specified in the function call. Default arguments can only supply a value of the same type as a parameter.
Function overloading: Function overloading is when two or more functions have the same name but different numbers or types of arguments. Overloaded functions can take different numbers and types of parameters. 

Upcasting and downcasting are types of object typecasting in Java that differ in the direction of the conversion:
Upcasting: Converts a subclass object to its superclass reference, allowing access to some of the parent class's methods and variables. Upcasting is also known as generalization and widening. The JVM does this implicitly at runtime.
Downcasting: Converts a superclass reference to its subclass object, allowing access to the methods of the child class. Downcasting is done explicitly by the programmer using the cast operator.